Yep, it is the same as in ZigBee. In order to deliver in the market Thread compliant devices you need to be member of the Thread Group (affiliate membership cost is 2500$) and pass the certifcation (validation includes: Commissioning, Network functionality and interoperability, Device operation in network) through UL Laboraties.

As start-up company I suggest you to have a look and apply for the Innovation Enabler Program that may(if approved) give you a free membership/certification. You can find all the details HERE.